[llvm-commits] CVS: llvm/lib/Bitcode/Writer/BitcodeWriter.cpp

Chris Lattner sabre at nondot.org
Sat May 5 00:36:43 PDT 2007



Changes in directory llvm/lib/Bitcode/Writer:

BitcodeWriter.cpp updated: 1.39 -> 1.40
---
Log message:

add abbrevs for the constants tables.  This shrinks it from 4.49755e6 bits
to 3.85972e6 bits in kc++


---
Diffs of the changes:  (+123 -61)

 BitcodeWriter.cpp |  184 ++++++++++++++++++++++++++++++++++++------------------
 1 files changed, 123 insertions(+), 61 deletions(-)


Index: llvm/lib/Bitcode/Writer/BitcodeWriter.cpp
diff -u llvm/lib/Bitcode/Writer/BitcodeWriter.cpp:1.39 llvm/lib/Bitcode/Writer/BitcodeWriter.cpp:1.40
--- llvm/lib/Bitcode/Writer/BitcodeWriter.cpp:1.39	Sat May  5 01:30:12 2007
+++ llvm/lib/Bitcode/Writer/BitcodeWriter.cpp	Sat May  5 02:36:14 2007
@@ -34,7 +34,13 @@
   VST_ENTRY_8_ABBREV = bitc::FIRST_APPLICATION_ABBREV,
   VST_ENTRY_7_ABBREV,
   VST_ENTRY_6_ABBREV,
-  VST_BBENTRY_6_ABBREV
+  VST_BBENTRY_6_ABBREV,
+  
+  // CONSTANTS_BLOCK abbrev id's.
+  CONSTANTS_SETTYPE_ABBREV = bitc::FIRST_APPLICATION_ABBREV,
+  CONSTANTS_INTEGER_ABBREV,
+  CONSTANTS_CE_CAST_Abbrev,
+  CONSTANTS_NULL_Abbrev
 };
 
 
@@ -396,11 +402,23 @@
 
 static void WriteConstants(unsigned FirstVal, unsigned LastVal,
                            const ValueEnumerator &VE,
-                           BitstreamWriter &Stream) {
+                           BitstreamWriter &Stream, bool isGlobal) {
   if (FirstVal == LastVal) return;
   
-  Stream.EnterSubblock(bitc::CONSTANTS_BLOCK_ID, 2);
+  Stream.EnterSubblock(bitc::CONSTANTS_BLOCK_ID, 4);
 
+  unsigned AggregateAbbrev = 0;
+  unsigned GEPAbbrev = 0;
+  // If this is a constant pool for the module, emit module-specific abbrevs.
+  if (isGlobal) {
+    // Abbrev for CST_CODE_AGGREGATE.
+    BitCodeAbbrev *Abbv = new BitCodeAbbrev();
+    Abbv->Add(BitCodeAbbrevOp(bitc::CST_CODE_AGGREGATE));
+    Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Array));
+    Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, Log2_32_Ceil(LastVal+1)));
+    AggregateAbbrev = Stream.EmitAbbrev(Abbv);
+  }  
+  
   // FIXME: Install and use abbrevs to reduce size.  Install them globally so
   // they don't need to be reemitted for each function body.
   
@@ -414,7 +432,8 @@
     if (V->getType() != LastTy) {
       LastTy = V->getType();
       Record.push_back(VE.getTypeID(LastTy));
-      Stream.EmitRecord(bitc::CST_CODE_SETTYPE, Record);
+      Stream.EmitRecord(bitc::CST_CODE_SETTYPE, Record,
+                        CONSTANTS_SETTYPE_ABBREV);
       Record.clear();
     }
     
@@ -437,6 +456,7 @@
         else
           Record.push_back((-V << 1) | 1);
         Code = bitc::CST_CODE_INTEGER;
+        AbbrevToUse = CONSTANTS_INTEGER_ABBREV;
       } else {                             // Wide integers, > 64 bits in size.
         // We have an arbitrary precision integer value to write whose 
         // bit width is > 64. However, in canonical unsigned integer 
@@ -466,6 +486,7 @@
       Code = bitc::CST_CODE_AGGREGATE;
       for (unsigned i = 0, e = C->getNumOperands(); i != e; ++i)
         Record.push_back(VE.getValueID(C->getOperand(i)));
+      AbbrevToUse = AggregateAbbrev;
     } else if (const ConstantExpr *CE = dyn_cast<ConstantExpr>(C)) {
       switch (CE->getOpcode()) {
       default:
@@ -474,6 +495,7 @@
           Record.push_back(GetEncodedCastOpcode(CE->getOpcode()));
           Record.push_back(VE.getTypeID(C->getOperand(0)->getType()));
           Record.push_back(VE.getValueID(C->getOperand(0)));
+          AbbrevToUse = CONSTANTS_CE_CAST_Abbrev;
         } else {
           assert(CE->getNumOperands() == 2 && "Unknown constant expr!");
           Code = bitc::CST_CODE_CE_BINOP;
@@ -488,6 +510,7 @@
           Record.push_back(VE.getTypeID(C->getOperand(i)->getType()));
           Record.push_back(VE.getValueID(C->getOperand(i)));
         }
+        AbbrevToUse = GEPAbbrev;
         break;
       case Instruction::Select:
         Code = bitc::CST_CODE_CE_SELECT;
@@ -540,7 +563,7 @@
   // We know globalvalues have been emitted by WriteModuleInfo.
   for (unsigned i = 0, e = Vals.size(); i != e; ++i) {
     if (!isa<GlobalValue>(Vals[i].first)) {
-      WriteConstants(i, Vals.size(), VE, Stream);
+      WriteConstants(i, Vals.size(), VE, Stream, true);
       return;
     }
   }
@@ -821,7 +844,7 @@
   // If there are function-local constants, emit them now.
   unsigned CstStart, CstEnd;
   VE.getFunctionConstantRange(CstStart, CstEnd);
-  WriteConstants(CstStart, CstEnd, VE, Stream);
+  WriteConstants(CstStart, CstEnd, VE, Stream, false);
   
   // Finally, emit all the instructions, in order.
   for (Function::const_iterator BB = F.begin(), E = F.end(); BB != E; ++BB)
@@ -875,6 +898,97 @@
   Stream.ExitBlock();
 }
 
+// Emit blockinfo, which defines the standard abbreviations etc.
+static void WriteBlockInfo(const ValueEnumerator &VE, BitstreamWriter &Stream) {
+  // We only want to emit block info records for blocks that have multiple
+  // instances: CONSTANTS_BLOCK, FUNCTION_BLOCK and VALUE_SYMTAB_BLOCK.  Other
+  // blocks can defined their abbrevs inline.
+  Stream.EnterBlockInfoBlock(2);
+  
+  { // 8-bit fixed-width VST_ENTRY/VST_BBENTRY strings.
+    BitCodeAbbrev *Abbv = new BitCodeAbbrev();
+    Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 3));
+    Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 8));
+    Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Array));
+    Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 8));
+    if (Stream.EmitBlockInfoAbbrev(bitc::VALUE_SYMTAB_BLOCK_ID, 
+                                   Abbv) != VST_ENTRY_8_ABBREV)
+      assert(0 && "Unexpected abbrev ordering!");
+  }
+  
+  { // 7-bit fixed width VST_ENTRY strings.
+    BitCodeAbbrev *Abbv = new BitCodeAbbrev();
+    Abbv->Add(BitCodeAbbrevOp(bitc::VST_CODE_ENTRY));
+    Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 8));
+    Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Array));
+    Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 7));
+    if (Stream.EmitBlockInfoAbbrev(bitc::VALUE_SYMTAB_BLOCK_ID,
+                                   Abbv) != VST_ENTRY_7_ABBREV)
+      assert(0 && "Unexpected abbrev ordering!");
+  }
+  { // 6-bit char6 VST_ENTRY strings.
+    BitCodeAbbrev *Abbv = new BitCodeAbbrev();
+    Abbv->Add(BitCodeAbbrevOp(bitc::VST_CODE_ENTRY));
+    Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 8));
+    Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Array));
+    Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Char6));
+    if (Stream.EmitBlockInfoAbbrev(bitc::VALUE_SYMTAB_BLOCK_ID,
+                                   Abbv) != VST_ENTRY_6_ABBREV)
+      assert(0 && "Unexpected abbrev ordering!");
+  }
+  { // 6-bit char6 VST_BBENTRY strings.
+    BitCodeAbbrev *Abbv = new BitCodeAbbrev();
+    Abbv->Add(BitCodeAbbrevOp(bitc::VST_CODE_BBENTRY));
+    Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 8));
+    Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Array));
+    Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Char6));
+    if (Stream.EmitBlockInfoAbbrev(bitc::VALUE_SYMTAB_BLOCK_ID,
+                                   Abbv) != VST_BBENTRY_6_ABBREV)
+      assert(0 && "Unexpected abbrev ordering!");
+  }
+  
+  { // SETTYPE abbrev for CONSTANTS_BLOCK.
+    BitCodeAbbrev *Abbv = new BitCodeAbbrev();
+    Abbv->Add(BitCodeAbbrevOp(bitc::CST_CODE_SETTYPE));
+    Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed,
+                              Log2_32_Ceil(VE.getTypes().size()+1)));
+    if (Stream.EmitBlockInfoAbbrev(bitc::CONSTANTS_BLOCK_ID,
+                                   Abbv) != CONSTANTS_SETTYPE_ABBREV)
+      assert(0 && "Unexpected abbrev ordering!");
+  }
+  
+  { // INTEGER abbrev for CONSTANTS_BLOCK.
+    BitCodeAbbrev *Abbv = new BitCodeAbbrev();
+    Abbv->Add(BitCodeAbbrevOp(bitc::CST_CODE_INTEGER));
+    Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 8));
+    if (Stream.EmitBlockInfoAbbrev(bitc::CONSTANTS_BLOCK_ID,
+                                   Abbv) != CONSTANTS_INTEGER_ABBREV)
+      assert(0 && "Unexpected abbrev ordering!");
+  }
+  
+  { // CE_CAST abbrev for CONSTANTS_BLOCK.
+    BitCodeAbbrev *Abbv = new BitCodeAbbrev();
+    Abbv->Add(BitCodeAbbrevOp(bitc::CST_CODE_CE_CAST));
+    Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 4));  // cast opc
+    Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed,       // typeid
+                              Log2_32_Ceil(VE.getTypes().size()+1)));
+    Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 8));    // value id
+
+    if (Stream.EmitBlockInfoAbbrev(bitc::CONSTANTS_BLOCK_ID,
+                                   Abbv) != CONSTANTS_CE_CAST_Abbrev)
+      assert(0 && "Unexpected abbrev ordering!");
+  }
+  { // NULL abbrev for CONSTANTS_BLOCK.
+    BitCodeAbbrev *Abbv = new BitCodeAbbrev();
+    Abbv->Add(BitCodeAbbrevOp(bitc::CST_CODE_NULL));
+    if (Stream.EmitBlockInfoAbbrev(bitc::CONSTANTS_BLOCK_ID,
+                                   Abbv) != CONSTANTS_NULL_Abbrev)
+      assert(0 && "Unexpected abbrev ordering!");
+  }
+  
+  Stream.ExitBlock();
+}
+
 
 /// WriteModule - Emit the specified module to the bitstream.
 static void WriteModule(const Module *M, BitstreamWriter &Stream) {
@@ -889,6 +1003,9 @@
   
   // Analyze the module, enumerating globals, functions, etc.
   ValueEnumerator VE(M);
+
+  // Emit blockinfo, which defines the standard abbreviations etc.
+  WriteBlockInfo(VE, Stream);
   
   // Emit information about parameter attributes.
   WriteParamAttrTable(VE, Stream);
@@ -927,58 +1044,6 @@
   Stream.ExitBlock();
 }
 
-// Emit blockinfo, which defines the standard abbreviations etc.
-static void WriteBlockInfo(BitstreamWriter &Stream) {
-  // We only want to emit block info records for blocks that have multiple
-  // instances: CONSTANTS_BLOCK, FUNCTION_BLOCK and VALUE_SYMTAB_BLOCK.  Other
-  // blocks can defined their abbrevs inline.
-  Stream.EnterBlockInfoBlock(2);
-  
-  { // 8-bit fixed-width VST_ENTRY/VST_BBENTRY strings.
-    BitCodeAbbrev *Abbv = new BitCodeAbbrev();
-    Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 3));
-    Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 8));
-    Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Array));
-    Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 8));
-    if (Stream.EmitBlockInfoAbbrev(bitc::VALUE_SYMTAB_BLOCK_ID, 
-                                   Abbv) != VST_ENTRY_8_ABBREV)
-      assert(0 && "Unexpected abbrev ordering!");
-  }
-  
-  { // 7-bit fixed width VST_ENTRY strings.
-    BitCodeAbbrev *Abbv = new BitCodeAbbrev();
-    Abbv->Add(BitCodeAbbrevOp(bitc::VST_CODE_ENTRY));
-    Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 8));
-    Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Array));
-    Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 7));
-    if (Stream.EmitBlockInfoAbbrev(bitc::VALUE_SYMTAB_BLOCK_ID,
-                                   Abbv) != VST_ENTRY_7_ABBREV)
-      assert(0 && "Unexpected abbrev ordering!");
-  }
-  { // 6-bit char6 VST_ENTRY strings.
-    BitCodeAbbrev *Abbv = new BitCodeAbbrev();
-    Abbv->Add(BitCodeAbbrevOp(bitc::VST_CODE_ENTRY));
-    Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 8));
-    Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Array));
-    Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Char6));
-    if (Stream.EmitBlockInfoAbbrev(bitc::VALUE_SYMTAB_BLOCK_ID,
-                                   Abbv) != VST_ENTRY_6_ABBREV)
-      assert(0 && "Unexpected abbrev ordering!");
-  }
-  { // 6-bit char6 VST_BBENTRY strings.
-    BitCodeAbbrev *Abbv = new BitCodeAbbrev();
-    Abbv->Add(BitCodeAbbrevOp(bitc::VST_CODE_BBENTRY));
-    Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 8));
-    Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Array));
-    Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Char6));
-    if (Stream.EmitBlockInfoAbbrev(bitc::VALUE_SYMTAB_BLOCK_ID,
-                                   Abbv) != VST_BBENTRY_6_ABBREV)
-      assert(0 && "Unexpected abbrev ordering!");
-  }
-  
-  Stream.ExitBlock();
-}
-
 
 /// WriteBitcodeToFile - Write the specified module to the specified output
 /// stream.
@@ -996,9 +1061,6 @@
   Stream.Emit(0xE, 4);
   Stream.Emit(0xD, 4);
 
-  // Emit blockinfo, which defines the standard abbreviations etc.
-  WriteBlockInfo(Stream);
-  
   // Emit the module.
   WriteModule(M, Stream);
   






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